The present invention relates to a crankshaft milling machine. More specifically, the present invention relates to an apparatus for supporting and driving the milling tool in a crankshaft milling machine. Such machines normally comprise a milling slide and a drive spindle rotatably supported in the milling slide. A milling tool carrying several, axially spaced disk cutters is also rotatably supported in the milling slide and operatively connectable to the drive spindle.
The spacing of the disk cutters from the spindle nose or end of the drive spindle is important for the precise spacing of the milled crankshaft bearings. Especially the position of the crankshaft thrust bearing depends on such spacing. Thus, the spacing between the disk cutters and the spindle end is adjusted as precisely as possible when the disk cutters are mounted on the milling tool.
However, such initial adjustment during the mounting of the milling tool cannot be maintained during the operation of the milling tool due to the heating of the milling tool as a result of its cutting operation. Such heating causes a lengthening of the milling tool so that the spacing between the individual disk cutters from the spindle nose is increased.
In prior art crankshaft milling machines the drive spindle was supported by an axial bearing which necessarily had to have a certain distance or spacing relative to the next adjacent portion of the milling tool. Thus, the heat expansion of the drive spindle already changes or varies the position of the spindle nose and thus generally the reference plane for the axial position of the disk cutters.